In recent years the number of electric motors and electric devices associated with truck boxes and trailers has increased. All of the motors and other electric devices on a truck box or trailer typically require DC current from a single battery located on the truck cab. Electric cables need to connect each of the motors and devices to the battery or other power source. Making multiple battery-to-motor connections individually requires the use of multiple, lengthy and expensive cables that tend to clog the wiring channels, if multiple cables can even fit in those channels.
In order to reduce the expense and burden of using multiple, lengthy cables between the battery and the electric motors or other devices, junction boxes have been employed. Such boxes used a single cable to create a power source at a more convenient location on the truck box or trailer devices in need of electricity. This reduced the expense of and channel clogging caused by multiple cables traversing the same path, but created other problems.
For example, connecting cables to the junction box is laborious as heavy cables need to be cut to length, stripped of insulation on each conductor and attached to terminals on the box. At the end of the cable attached to an electric motor or device, each conductor needed to be stripped and crimped or soldered onto heavy duty ring terminals. These operations require special tools and extra installation labor, and can be time consuming and expensive to perform.
Electric motors and devices are often added to a truck box or trailer after it is manufactured and delivered, i.e., as a retrofit product or accessory. This increases the difficulty of wiring as the original arrangement may not accommodate the addition of more cables and connections to the junction box. Moreover, retrofit additions of motors or other devices requires that modifications be made by persons (such as equipment operators) in the field who may not be experienced with electrical connectors or wiring, and under challenging circumstances, uncomfortable weather or difficult working conditions.
In addition, in use, truck boxes and trailers experience extreme ambient temperatures combined with moisture, constant high winds, direct sunlight, road salt, and de-icing or other chemicals. As a result, junction boxes, and wiring, ring terminals and other connections on the truck boxes or trailers are subject to corrosion and relatively high failure rates over time. Hence, conventional wiring arrangements on truck boxes and trailers present a number of problems.